<!DOCTYPE html>
<html>
<meta charset="utf-8">
<style>
body>div { margin: 50px 20px; width: 120px; height: 150px; border: 5px solid blue; }
.vlr { writing-mode: vertical-lr; }
.rel { position: relative; }
span { display: inline-block; padding: 5px; block-size: 1.5em; border: 2px solid red; }
p { position: absolute; margin: 0; padding: 2px; border: 2px solid green; }
</style>
<body>
<div class="vlr">
  <div class="rel"><span>abc def</span><p>xyzzy</p></div>
</div>
